Ethyl acetate absolute

A blend of botanical extracts natural chemicals, ie, isolates and those derived via natural processes, eg, ethyl acetate, absolute tagette and oil petitigrain mandarin. 

Thin layer chromatography has proven to be a useful and efficient means of identification, separation, and purity examination of vincristine sulfate or the free base. The reader is referred to Section 4.4 of the Vinblastine Sulfate profile in this publication which contains several TLC methods and references applicable to vincristine sulfate or the free base. Cone e t al.19 have reported the separation of vincristine, leurosidine, and either vinblastine or leurosine as free bases on alumina by developing first in 100% ethyl acetate followed by a second development in ethyl acetate-absolute ethanol (3 1) Svoboda also used this system1 and reported Rf values as follows 0.54 for vincristine, 0.37 for... 

Solvent I = Chloroform-ethyl acetate (60 -f 60) II = Ethyl acetate-absolute ethanol (76 + 26) III = Ethyl acetate-absolute ethanol (50 + 60) IV = Pure ethyl acetate. 

Ethyl acetate. Use 58 g. (73-5 ml.) of absolute ethyl alcohol, 225 g. of glacial acetic acid and 3 g. of concentrated sulphuric acid. Reflux for 6-12 hours. Work up as for n-propyl acetate. B.p. 76- 77°. Yield 32 g. Much ethyl acetate is lost in the washing process. A better yield may be obtained, and most of the excess of acetic acid may be recovered, by distilhng the reaction mixture through an efficient fractionating column and proceeding as for methyl acetate. 

It is important to use dry ethyl acetate, but it should contain 2-3 per cent, of alcohol. The so-called absolute or anhydrous ethyl acetate of commerce is satisfactory. Experimental details for the purification of 95-97 p>er cent, ethyl acetate are given in Section 11,47,29. 

Allow a mixture of 0-5 g. of the tertiary amine and 0-5 ml. of colourless methyl iodide to stand for 5 minutes. If reaction has not occurred, warm under reflux for 5 minutes on a water bath and then cool in ice water. The mixture will generally set solid if it does not, scratch the sides of the tube with a glass rod. RecrystaUise the solid product from absolute alcohol, ethyl acetate, acetone, glacial acetic acid or alcohol-ether. 

Method B. Place 125 g. (106 -5 ml.) of diethyl phthalate and 25 g. of molecular sodium (sodium sand see Section 11,50,6) in a 500 ml. round-bottomed flask fitted with a reflux condenser and dropping funnel. Heat the flask on a steam bath and add a mixture of 122 5 g. (136 ml.) of dry ethyl acetate and 2 5 ml. of absolute ethanol over a period of 90 minutes. Continue the heating for 6 hours, cool and add 50 ml. of ether. Filter the sodium salt (VI) on a sintered glass funnel and wash it with the minimum volume of ether. Dissolve the sodium salt (96 g.) in 1400 ml. of hot water in a 3-htre beaker, cool the solution to 70°, stir vigorously and add 100 ml. of sulphuric acid (3 parts of concentrated acid to 1 part of... 

Crystd from absolute EtOH/ethyl acetate. It is hygroscopic. 

Broirjal has been prepared by brominating a solution of paraldehyde in ethyl acetate, and by passing bromine vapor through absolute alcohol. ... 

The crude ketal from the Birch reduction is dissolved in a mixture of 700 ml ethyl acetate, 1260 ml absolute ethanol and 31.5 ml water. To this solution is added 198 ml of 0.01 Mp-toluenesulfonic acid in absolute ethanol. (Methanol cannot be substituted for the ethanol nor can denatured ethanol containing methanol be used. In the presence of methanol, the diethyl ketal forms the mixed methyl ethyl ketal at C-17 and this mixed ketal hydrolyzes at a much slower rate than does the diethyl ketal.) The mixture is stirred at room temperature under nitrogen for 10 min and 56 ml of 10% potassium bicarbonate solution is added to neutralize the toluenesulfonic acid. The organic solvents are removed in a rotary vacuum evaporator and water is added as the organic solvents distill. When all of the organic solvents have been distilled, the granular precipitate of 1,4-dihydroestrone 3- methyl ether is collected on a filter and washed well with cold water. The solid is sucked dry and is dissolved in 800 ml of methyl ethyl ketone. To this solution is added 1600 ml of 1 1 methanol-water mixture and the resulting mixture is cooled in an ice bath for 1 hr. The solid is collected, rinsed with cold methanol-water (1 1), air-dried, and finally dried in a vacuum oven at 60° yield, 71.5 g (81 % based on estrone methyl ether actually carried into the Birch reduction as the ketal) mp 139-141°, reported mp 141-141.5°. The material has an enol ether assay of 99%, a residual aromatics content of 0.6% and a 19-norandrost-5(10)-ene-3,17-dione content of 0.5% (from hydrolysis of the 3-enol ether). It contains less than 0.1 % of 17-ol and only a trace of ketal formed by addition of ethanol to the 3-enol ether. 

Reduction of 17a-EthynyI to 17a-Ethyl °° A solution of 5 g of 17a-ethynyl-androst-5-ene-3j9,17j5-diol in 170 ml of absolute alcohol is hydrogenated at atmospheric pressure and room temperature using 0.5 g of 5 % palladium-on-charcoal catalyst. Hydrogen absorption is complete in about 8 min with the absorption of 2 moles. After removal of the catalyst by filtration, the solvent is evaporated under reduced pressure and the residue is crystallized from ethyl acetate. Three crops of 17a-ethylandrost-5-ene-3) ,17j9-diol are obtained 3.05 g, mp 197-200° 1.59 g, mp 198.6-200.6° and 0.34 g, mp 196-199° (total yield 5.02 g, 90%). A sample prepared for analysis by recrystallization from ethyl acetate melts at 200.6-202.4° [aj, —70° (diox.). 

The hydrochloride is prepared in the usual manner by dissolving the amine in anhydrous ether and adding to it the requisite amount of dry gaseous hydrochloric acid,dissolved in absolute alcohol. There is obtained a white crystalline powder melting at 150°C, very soluble in water and alcohol,very slightly soluble in ether and ethyl acetate. 

The crude product (48.4 grams, 80.9% yield) was recrystallized from an absolute ethanol-ethyl acetate solvent system by suspending the salt in boiling anhydrous ethyl acetate and just enough absolute ethanol was gradually added to effect solution after which the solu-... 

C) Preparation of Doxapram Hydrochloride [3,3-Diphenyl-1-Ethyl-4-(2-Morpholino-Ethylj-2-Pyrrolidinone Hydrochloride Monohydrate] A solution of 25 grams (0.076 mol) of 4-(2-chloroethyl)-3,3-diphenyl-1-ethyl-2-pyrrolidinone and 13.3 grams (0.153 mol) of morpholine in 500 ml of absolute ethanol was heated at 95°-120°C for 21 hours in a closed system and concentrated in vacuo. The residue was dissolved in 3(X) ml of two normal hydrochloric acid and extracted with 150 ml of ethyl acetate. A solid crystallized (13 g) during the extraction and was removed by filtration. MP 217°-219°C. The acid extracts were made basic with sodium hydroxide and extracted with ether, and the ether solution was concentrated in vacuo and the residue was suspended in six normal hydrochloric acid. Additional crystalline product formed and was recrystallized from two normal hydrochloric acid. Yield, 10 grams MP 217°-219°C. Total yield, 23 grams (70%). 

After evaporation of the solvent, a very thick, colorless oil is obtained. This base is dissolved by 200 ml of absolute ethanol and the quantity of HCI to obtain the dihydrochioride is added. It is left for a few hours over ice, dried, washed with approximately 100 ml of anhydrous ether in order to obtain 190 to 195 grams of 1-[2-phenyl-2-methoxy]-ethyl-4-[3-phenyl-3-hydroxy] -propyl-piperazine dihydrochioride after drying at 60°C in vacuo. The yield is 80%. It is recrystallized from absolute ethanol. The product is in the form of white crystalline powder, soluble in water, slightly soluble in alcohol, insoluble in ethyl acetate. 

To a solution of 13 parts of compound A and 12 parts by volume of absolute pyridine in 80 parts by volume of absolute dioxane there are added dropwise and under constant stirring 35 parts of 3,4.5-trimethoxybenzoyl chloride dissolved in 70 parts by volume of absolute dioxane in the course of 30 minutes. The mixture is stirred for a further 3 hours at a temperature of 100°C and the excess solvent is then evaporated in vacuo. The residue of the evaporation is treated with ethyl acetate and saturated sodium carbonate solution, whereafter the organic phase is separated, treated with water, dried with sodium sulfate and the solvent is removed in vacuo. The residue thus obtained is taken up In ether and separated from 4 parts of insoluble trimethoxybenzoic acid anhydride by filtration. After evaporation of the ether there are obtained 32.5 parts of N,N -dimethyl-N,N -bis-[3-(3,4,5-trlmethoxybenzoxy)-propyl] -athylene diamine, corresponding to a yield of 86% of the theoretical. MP 75°C to 77°C. 

As described in U.S. Patent 2,507,631, 80 g of pulverized sodium amide are gradually added, while stirring and cooling, to a solution of 117 g of phenyl-acetonitrile and 113 g of 2-chloropyridine in 400 cc of absolute toluene. The mixture is then slowly heated to 110° to 120°C and maintained at this temperature for 1 hour. Water is added thereto after cooling, the toluene solution is shaken with dilute hydrochloric acid and the hydrochloric acid extracts are made alkaline with concentrated caustic soda solution. A solid mass is separated thereby which is taken up in acetic ester and distilled, a-phenyl-a-pvridyl-(2)-acetonitrile passing over at 150° to 155°C under 0.5 mm pressure. When re-crystallized from ethyl acetate it melts at 88° to 89°C, the yield amounting to 135 g. 

A mixture of 114.5 g of 5-(3-chloropropylidene)dlbenzo[a i] cyclohepta[1,4] diene, 75 ml of benzene, and about 400 ml of methylamine is heated in an autoclave at 120°Cfor six hours. The excess methylamine is distilled from the reaction mixture under vacuum and the residue is stirred with 300 ml of water. Acidification of the mixture with hydrochloric acid causes the separation of the hydrochloride of 5-(3-methylaminopropylidene)dlbenzo[a,dlcyclo-hepta[ 1,4] diene. The product is collected by filtration and is purified by recrystallizatlon from a mixture of absolute ethanol and ethyl acetate. MP 210°C to 212 C. 

The solvent used is an important factor influencing the rate of reduction 34 and no generalization can be made beyond the one that alcohol, either 95 per cent or absolute has proved to be the best solvent for most of the compounds thus far studied. Ethyl acetate and glacial acetic acid may be used to advantage in some cases. 

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